MIAMI - SEPTEMBER 23: University of Miami Pediatrician Endocrinologist Dr. Janine Sanchez examines Roberto V. Murillo,13, in an examination room at the University of Miami Leonard M. Miller School of Medicine on September 23, 2010 in Miami, Florida. As U.S. President Barack Obama's health care changes take effect today, Roberto's mother Veronica Macias and father Roberto A. Murillo don't have to worry about not finding insurance for their son who has diabetes because insurance companies have to insure people with pre-existing conditions. Dr. Sanchez felt the new health care laws are positive given that patients don't have to worry about not being able to find coverage.Examination in a doctor's office. (Joe Raedle/Getty Images)

SAN FRANCISCO (CBS/AP) — Many Anthem Blue Cross customers could see their rates jump an average of 18 percent in February, under a proposal by the state’s largest for-profit health insurer.

The proposed increases could affect 630,000 individual policyholders, some of whom may see premiums rise as much as 25 percent. In its rate request, Anthem cited rising medical costs.

The rate hikes are among several others proposed by California insurers, including Aetna and Health Net.

KCBS’ Rebecca Corral Reports:

Insurance regulators will review the proposals, but state officials don’t have the authority to reject them for being unreasonable.

In 2010, Anthem was forced to back down from a proposed 39 percent rate increase.

This year Anthem has raised premiums up to 14 percent on average, for about 700,000 individual policyholders.

Other insurers are also proposing rate hikes.

Athena was planning a nearly 19 percent rate hike for nearly 70,000 members with individual policies in April.

Kaiser Permanento also wants to raise rates by 8 percent for 220,000 members in January.

In January, UnitedHealth Group proposed 10 percent hikes for over 10,000 policyholders.

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